Basic protein- and peptide-induced stabilization of long-loop DNA G-guadruplexes

The human genome contains many G-quadruplex-forming sequences, including sequences containing long single-stranded loops that are believed to be unfavorable for G-quadruplex formation. The intracellular environment of biological cells is crowded with proteins with charged surfaces. Understanding the effects of protein-rich environments is important for understanding the formation of G-quadruplexes in an intracellular environment. In this study, we investigated the structural stability of DNA G-quadruplexes in the presence of several types of globular proteins (lysozyme, cytochrome c, bovine serum albumin, myoglobin, histone proteins, and serum proteins), unstructured polypeptides (protamine and poly-l-lysine), and oligopeptides (RGG/RG-domain peptides and short repeated peptides). Thermal melting studies of G-quadruplex-forming oligonucleotides derived from the human telomeric repeat sequence revealed that environments containing high concentrations of proteins and peptides differently affected the G-quadruplex stability according to their loop lengths. We found that weak electrostatic interactions of G-quadruplex loops with basic proteins and peptides improved the stability of long-loop G-quadruplexes and the interactions were strengthened under crowded conditions simulated by dextran. The comparison of the effects of different types of proteins and peptides indicated that excluded volume interactions and structural flexibility of both DNA and polypeptide chains influenced the efficiency of their interactions. This study provides insights into long-loop G-quadruplex stability in a crowded intracellular environment and the recognition of G-quadruplexes by arginine-rich domains of G-quadruplex-binding proteins.

P-215 Use of hyaluronan-based solution as an alternative to polyvinylpyrrolidone to improve blastulation in ICSI

Study question

This study aimed to analyze whether hyaluronan as an alternative to polyvinylpyrrolidone (PVP) for sperm immobilization, aspiration, and injection into the ooplasm improves ICSI outcomes.

Summary answer

The use of hyaluronan solution as an alternative to PVP improves the blastocyst formation rate and good quality blastocyst formation rate compared to PVP.

What is known already

The PVP solution facilitates ICSI procedures, such as sperm immobilization, aspiration, and injection into the ooplasm. However, it has been reported that injection of a small amount of PVP along with the sperm into the ooplasm negatively affects subsequent embryo development. Hyaluronan is a natural component of the extracellular matrix of the cumulus-oocyte complex. Balaban et al. (2003) reported that hyaluronan can replace PVP during ICSI procedures in the early embryo transfer cycle without adversely affecting pregnancy outcomes. This study analyzed whether using hyaluronan-based solution for the ICSI procedure would improves blastocyst development compared with ICSI using PVP.

Study design, size, duration

This retrospective study analyzed clinical medical reports at Takahashi Women’s Clinic, Japan. We included 4002 oocytes retrieved from 411 patients under 39 years of age who underwent ICSI using autologous oocytes between December 2019 and August 2021. Of the oocytes used for ICSI, 1909 underwent sperm aspiration and injection into the ooplasm with hyaluronan (Sperm Slow; Origio), and 2093 oocytes with 7% PVP (NakaMedical). We did not perform preimplantation genetic testing-aneuploidy for any cycles.

Participants/materials, setting, methods

We used PVP droplets for sperm selection under 400× magnification in both groups. In hyaluronan-ICSI, the selected sperm were transferred to a hyaluronan droplet and washed three times. The sperm was then aspirated with hyaluronan, and ICSI was performed. In PVP-ICSI, all procedures were performed using PVP. The ICSI and embryo transfer outcomes were compared between hyaluronan-ICSI and PVP-ICSI by logistic regression analysis considering patient age, BMI, and basal level of anti-mullerian hormone.

Main results and the role of chance

Normal fertilization rates were 74.3% (1556/2093) in PVP-ICSI and 75.5% (1442/1909) in hyaluronan-ICSI. There was no significant difference in the normal fertilization rate between PVP-ICSI and hyaluronan-ICSI groups (p = 0.437, aOR:1.06, 95% CI: 0.92–1.22). We cultured 1323 2PN embryos in PVP-ICSI and 1237 2PN embryos in hyaluronan-ICSI until the blastocyst stage. Blastocyst formation rates were 48.1% for PVP-ICSI and 52.3% for hyaluronan-ICSI, and this difference was statistically significant (aOR, 1.20; 95% CI: 1.02–1.40; p = 0.024). Moreover, the good grade (Gardner criteria ≧BB) blastocyst formation rates were significantly higher in the hyaluronan-ICSI group (36.9% and 41.0%, aOR: 1.21, 95% CI: 1.03–1.42, p = 0.022). During the study period, we performed 163 and 169 cryo-thawed blastocyst transfer cycles in PVP-ICSI and hyaluronan-ICSI, respectively. The clinical pregnancy rate (50.9% vs. 54.4%, aOR: 1.19, 95% CI: 0.77–1.83, p = 0.443) and miscarriage rate (19.3% vs. 13.0%, aOR: 0.66, 95% CI: 0.3–1.44, p = 0.295) after embryo transfer were not significantly different between PVP-ICSI and hyaluronan-ICSI.

Limitations, reasons for caution

The study was conducted at a single IVF center, and the oocytes included in this study were collected from patients aged < 39 years. Embryo transfer result is based on ongoing pregnancy, while the live birth data for all pregnancies are not yet available.

Wider implications of the findings

Hyaluronan facilitates ICSI procedures such as sperm immobilization, aspiration, and injection. Moreover, the hyaluronan improves blastocyst development. The present study indicates that using hyaluronan as an alternative to PVP during the ICSI procedure is recommended.

Trial registration number

not applicable

P-395 Use of a granulocyte-macrophage colony-stimulating factor (GM-CSF)-containing medium for poor-grade blastocyst transfer increases the clinical pregnancy and live birth rates

Study question

Does the post-thaw use of a GM-CSF-containing medium improve blastocyst transfer outcomes in all blastocysts in a frozen-thawed embryo transfer cycle?

Summary answer

The use of a GM-CSF-containing medium at post-thawing especially improves the live birth (LB) rate of morphologically poor blastocysts in a frozen-thawed embryo transfer cycle.

What is known already

GM-CSF, a cytokine secreted by the epithelial cells of the female reproductive tract, plays an important role in embryonic development, implantation, and subsequent development in humans and animals. In humans, GM-CSF increases the blastocyst developmental rate and decreases the chances of miscarriage. Previously, we reported that the use of a GM-CSF-containing medium for blastocyst recovery culture after thawing improves the clinical pregnancy (CP) rate in a frozen-thawed blastocyst transfer cycle (ESHRE, 2019). However, it is unclear whether GM-CSF improves embryo transfer outcomes in all blastocysts. In addition, it is necessary to accumulate information regarding its effects on neonatal outcomes.

Study design, size, duration

We performed a retrospective observational study to compare two groups: a GM-CSF group (GM-CSF-containing medium; SAGE-1step GM-CSF, Cooper Surgical) and a control group (GM-CSF-free medium; ONE STEP Medium, NAKA Medical). We analyzed 566 blastocyst transfer cycles in patients aged 30–39 years who underwent frozen-thawed single embryo transfer at Takahashi Women’s Clinic (Japan) from February 2018 to February 2019. Chromosomal analysis was not performed.

Participants/materials, setting, methods

We used a control medium for blastocyst culture and a Cryotop safety kit for blastocyst vitrification. After thawing, we cultured blastocysts in a GM-CSF-containing medium or control medium for 3–5 h until transfer. Embryo transfer outcomes were compared. We performed the multivariate logistic regression analysis(MVRA) to adjust confounding bias. A subgroup analysis was also performed of morphological grade according to Gardner’s criteria (excellent: ≥AA, good: blastocysts containing B, poor: blastocysts containing C).

Main results and the role of chance

There were no difference in patient background between the two groups. The CP and LB rates in the GM-CSF group and control group were 54.3% vs. 42.6% and 42.9% vs. 31.1%. The MVRA adjusted by confounding factors(patient age, BMI, basal AMH, blastocyst grade, day of vitrification, number of previous failed ETs, and assisted hatching) demonstrated that CP (p = 0.0193; adjusted odds ratio [aOR], 1.55) and LB rate (p = 0.0080; aOR, 1.67) were significantly higher in GM-CSF group than that of control group. Moreover, the CP and LB rates of the GM-CSF group and control group were: excellent-blastocysts at 62.0% vs. 58.8% (p = 0.5955; OR, 1.14), 52.7% vs. 45.6% (p = 0.2466, aOR:1.33), good-blastocysts 52.1% vs. 37.6% (p = 0.0561; OR, 1.80), 38.0% vs. 26.6% (p = 0.1072; OR, 1.69), and poor-blastocysts 38.9% vs. 17.9% (p = 0.0115; OR, 2.92), 25.9% vs. 9.0% (p = 0.0164; OR, 3.56). A GM-CSF-containing medium significantly improved the CP and LB rates of poor-grade blastocysts. There were no significant differences between the GM-CSF group and control group in the male ratio (52.7％ vs. 51.0%, p = 0.8057), pregnancy duration (38.8±1.4 weeks vs. 38.5±1.8 weeks, p = 0.2558), cesarean section rate (38.2% vs. 40.8%, p = 0.6979), birth weight (3133±466g vs. 3037±437g, p = 0.1281), and congenital anomaly rate (0.91% vs. 2.04％, p = 0.6026).

Limitations, reasons for caution

This was a single-center, retrospective study. Chromosomal abnormalities in embryos were not considered; however, the LB rate among babies was analyzed. The basic chemical composition of the culture medium (salt concentration, glucose concentration, etc.) used in the control group was different from that of the GM-CSF-containing medium.

Wider implications of the findings

We found that the use of a GM-CSF-containing medium improved the clinical pregnancy and live birth rates of poor-grade blastocysts without affecting the babies. This may be an effective therapeutic strategy for some patients as it may allow for the effective use of poor-grade euploid blastocysts.

Trial registration number

not applicable

Influences of smoking on central blood pressure in hypertensive subjects

Background/Introduction

Smoking is known to induce systemic vascular damage, leading to cardiovascular diseases. Recent studies demonstrated that central blood pressure has a greater impact on cardiovascular events than brachial blood pressure.

Purpose

We investigated influences of habitual smoking on central systolic blood pressure (CSBP) in hypertensive subjects.

Methods

A total of 5630 subjects (male = 2622, 51.7±12.0 year-old at baseline), who visited our hospital for a physical check-up at least twice during the last 10 years and underwent CSBP measurement at each visit, were enrolled, and they were divided into three groups; normotensive (n=4634), non-treated hypertensive (n=91) and treated hypertensive subjects (n=905). Then, the influences of smoking on the average and yearly changes of CSBP (median follow-up 5 years) were analyzed. Brachial blood pressure (oscillometer) and radial artery pressure waveforms (tonometer) were recorded using an automated device, and the pressure corresponding to the second systolic peak of radial pressure waveforms was taken as CSBP (HEM-9000AI, Omron Healthcare, Kyoto). Hypertension was defined as brachial BP ≥140/90mmHg or the use of antihypertensive medications. A yearly change in CSBP was calculated in each subject by linear regression analysis using longitudinal data.

Results

The average CSBP was higher in habitual smokers than in non-smokers when analyzed in normotensive (109.1±11.7 vs. 107.6±12.8 mmHg, p<0.001) and non-treated hypertensive subjects (150.7±14.8 vs. 142.8±16.7 mmHg, p<0.05), whereas in hypertensive subjects under medication the average CSBP was lower in smokers than in non-smokers (124.6±12.4 vs. 127.8±13.6 mmHg, p<0.01). Smoking status did not affect yearly changes of CSBP in normotensive (habitual smokers vs. non-smokers; 1.38±6.00 vs. 1.44±6.04 mmHg/year), treated hypertensive (−0.16±7.08 vs. −0.66±8.24 mmHg/year), and non-treated hypertensive subjects (4.09±15.1 vs. −0.53±10.3 mmHg/year).

Conclusions

Habitual smoking increases CSBP, however, antihypertensive medications counteract the unfavorable effects of smoking on CSBP. These results imply a new pathway underlying the development of cardiovascular diseases in smokers. Unfavorable changes in the cardiovascular system caused by smoking may quite slowly progress that short period of observation in the present study could not have detected enhanced yearly increases of CSBP by smoking.

Funding Acknowledgement

Type of funding sources: None.

Diagnostic performance of fractional flow reserve derived from computed tomography in the stented coronary arteries

Background

The current system of HeartFlow fractional flow reserve derived from computed tomography (FFRCT) is not available for stented coronary arteries. However, the latest version of HeartFlow FFRCT has the potential of rendering an accurate assessment for stented coronary arteries.

Objectives

To evaluate the feasibility of FFRCT for the stented coronary arteries.

Methods

We retrospectively enrolled patients with a history of coronary stent implantation who underwent invasive fractional flow reserve (FFR) for the stented coronary arteries within 3 months after coronary computed tomographic angiography (cCTA). As a subgroup analysis, we analyzed optical coherence tomography (OCT) images in patients who underwent OCT for stented vessels. OCT was performed as a part of the Kobe University Hospital OCT registry, which is a single-centre registry of consecutive patients who underwent OCT for the coronary arteries. The diagnostic performance of HeartFlow FFRCT for stented vessels was evaluated by comparing with that of cCTA alone. Minimum lumen area (MLA) within stent segments derived from cCTA was also compared with MLA derived from optical coherence tomography (OCT).

Results

A total of 30 vessels in 23 patients were studied. The diagnostic accuracy, sensitivity, specificity, positive and negative predictive value of FFRCT for myocardial ischemia using invasive FFR as a reference standard was 73.3%, 88.9%, 67.7%, 53.3% and 93.3%, respectively. FFRCT provided superior diagnostic performance than cCTA alone (p=0.016). FFRCT was significantly correlated with the invasive FFR (r=0.620, p<0.001), and Bland-Altman plot showed a mean bias of −0.041 with 95% limit of agreement of −0.173 to 0.092 (Figure 1). Among a total of 30 studied vessels, OCT was available for 25 vessels. MLA derived from cCTA correlated significantly with that derived from OCT (r=0.695, p<0.001), and Bland-Altman plot showed a mean bias of −0.32 mm2 with 95% limit of agreement of −2.89 to 2.25 mm2 (Figure 2).

Conclusions

The latest version of the HeartFlow FFRCT has the potential to be available for stented coronary arteries. Further investigation is required to elaborate our results.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

“Target Heart Rate” calculated aiming at zero overlap of mitral E and A waves is useful for prediction of long-term outcome for patients with heart failure and reduced ejection fraction

Background

Lower heart rate (HR) is associated with more favourable long-term outcome in patients with heart failure with reduced ejection fraction (HFrEF). However, an optimal threshold of HR remains unclear. Targeted HR (THR), defined by echocardiographic deceleration time (DCT) to eliminated overlap of E and A waves, may aid in risk stratification of HFrEF patients.

Purpose

In this study, we aimed to clarify the impact of on long-term clinical outcome in patients with HFrEF.

Methods

In the multicenter WET-HF registry, 4000 consecutive patients hospitalized for acute decompensated HF (ADHF) were registered between 2006 and 2017. Among them, the patients with EF ≥40% or a history of atrial fibrillation were excluded. THR was calculated based on their DCT value measured in compensated HF phase during the index admission. The following formula was applied; THR (bpm)=93 - 0.13 × deceleration time (DCT, msec). A total of 876 patients with HFrEF were included in the present analysis (age: 72 [60–81], male: 69%) and the patients were divided into the 2 groups of HR at discharge ≤ THR (L group) and > THR (H group). The primary endpoint (PE) was defined as the composite of all-cause death and ADHF re-admission.

Results

Compared to the H group, the L group showed higher prevalence of males (74% vs. 66%, P=0.025) with higher body mass index (BMI, 23.2 vs. 22.2, P=0.016), hemoglobin (Hb, 12.9 vs. 12.4, P=0.031), albumin (Alb, 3.7 vs. 3.6, P=0.039) and larger left atrial diameter (LAD, 44 mm vs. 41 mm, P=0.002) and tricuspid regurgitation pressure gradient (TRPG, 29 mmHg vs. 27 mmHg, P=0.012). Age, estimated glomerular filtration rate (eGFR), LVEF (29% vs. 30%, P=NS) and E/e' (17.7 vs. 16.8, P=NS) were similar for both groups. At discharge, HR was lower in L group (66 [60–71] bpm vs. 80 [74–86] bpm, P<0.001), albeit there were no significant differences in b-blocker prescription (90% vs. 85%, P=0.069) or its dose (3.75 [1.25–7.25] mg vs. 2.5 [1.25–5] mg, P=0.11).

In the survival analysis, the L group showed a significantly lower rate of PE (P=0.03), whereas there was no significant difference in the incidence of PE between the patients with HR at discharge ≥70 bpm and <70 bpm (P=NS).

Multivariate Cox hazard analysis showed that HR at discharge ≤ THR was an independent predictor of PE (hazard ratio 0.67 [0.46–0.97], P=0.037), even after adjusting for confounding factors including age, sex, BMI, Hb, Alb, and b-blocker prescription, whereas HR at discharge <70 bpm was not (hazard ratio 0.94 [0.65–1.33], P=0.71).

Conclusion

THR was associated with long-term outcomes in patients with HFrEF after acute decompensation, suggesting that it may aid in tailored treatment for HR reduction in these patients.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

P–145 usefulness of morphokinetic data to predict pregnancy rates of day–6 blastocyst transfers

Study question

Can a scoring model based on morphokinetic data developed to predict pregnancy rates of day–5 blastocyst transfers (KIDSCORE™D5) predict pregnancy rates of day–6 blastocyst transfers?

Summary answer

KIDSCORE™D5 was able to predict the clinical pregnancy rates of embryo transfers done on day 6 with an area under the curve (AUC) of 0.72.

What is known already

KIDSCORE™D5 is a scoring model based on morphokinetic data developed to predict the pregnancy rates of day–5 blastocysts. In 2019, Regnier et al. reported that the AUC of KIDSCORE™D5 for predicting clinical pregnancy rates of day–5 blastocyst transfers was 0.6. However, as KIDSCORE™D5 is constructed based on morphological characteristics and developmental dynamics of day–5 blastocysts, it is unclear whether KIDSCORE™D5 can predict pregnancy rates of day–6 blastocyst transfers. Since there are many cases of day–6 blastocyst transfers, it is important to know if KIDSCORE™D5 can predict pregnancy rates of day–6 blastocyst transfers.

Study design, size, duration

This retrospective single-center study, which included 162 day–5 and 72 day–6 blastocyst transfers, respectively, was conducted at Takahashi Women’s clinic from January to December 2019. Blastocysts derived from 146 patients who underwent intracytoplasmic sperm injection. All blastocysts were cryopreserved and were transferred singly.

Participants/materials, setting, methods

We used EmbryoScope+™ (Vitrolife) for in-vitro culture and calculated KIDSCORE™D5 (ver.3) using Embryoviewer™ (Vitrolife). Blastocyst scoring was done from 1.0 to 9.9. Clinical pregnancy was defined as the presence of a gestational sac confirmed by transvaginal ultrasonography. Statistical analysis was performed with JMP Pro 15.00 (SAS). The relationship between KIDSCORE™D5 and clinical pregnancy was evaluated by the AUC using ROC curve analysis and multivariate analysis adjusted for patient age.

Main results and the role of chance

The mean KIDSCORE™D5 of day–5 and day–6 blastocysts was 7.1±1.7 and 3.7±1.5, respectively. KIDSCORE™D5 of day–6 blastocysts was significantly lower than that of day–5 blastocysts (p < 0.0001, Wilcoxon test). ROC curve analysis showed that the KIDSCORE™D5 could predict clinical pregnancy rates with an AUC of 0.62 for day–5 blastocysts and 0.72 for day–6 blastocysts. The cut-off values for KIDSCORE™D5 were 5.7 and 4.9 for day–5 and day–6 blastocysts, respectively. Blastocysts above the cut off value on both day–5 and day–6 had a significantly higher pregnancy rate than those below the cut off value (day–5: 61.9% vs. 33.3%(p = 0.0023), day–6: 47.4% vs. 7.6%(p = 0.0003)). Multivariate analysis adjusted for patient age showed that KIDSCORE™D5 correlated with clinical pregnancy rates of days 5 and 6 of blastocyst transfer with AUCs of 0.66 and 0.73, respectively.

Limitations, reasons for caution

This study had a small sample size, and it was a retrospective single-center study. In addition, the relationship between KIDSCORE™D5 and clinical pregnancy rates may vary among facilities. Therefore, a prospective multicenter validation is necessary.

Wider implications of the findings: Our study results indicated that KIDSCORE™D5 predicted clinical pregnancy and that morphokinetic parameters related to clinical pregnancy were similar between day–5 and day–6 blastocysts. Hence, morphokinetic evaluation can serve as a criterion for deciding which of multiple day–6 blastocysts can be transferred.

Trial registration number

Not applicable

Impact of tumor growth rate during preceding treatment on tumor response to nivolumab or irinotecan in advanced gastric cancer

Background

Nivolumab (NIVO) and irinotecan (IRI) are standard treatments for refractory advanced gastric cancer (AGC); however, it is unclear which drug should be administered first or in which cases. The tumor growth rate (TGR) during preceding treatment is reported to be associated with tumor response in metastatic colorectal cancer patients treated with regorafenib or trifluridine/tipiracil, suggesting that TGR may be useful for drug selection. Therefore, we evaluated the association between TGR during preceding treatment and the tumor response to NIVO or IRI.

Patients and methods

We retrospectively evaluated consecutive AGC patients treated with NIVO or IRI and divided them into slow-growing (Slow) and rapid-growing (Rapid) groups according to TGR and the presence or absence of new lesions (NL+/NL−, respectively) during preceding treatment (Slow group: NL− with low TGR <0.30%/day; Rapid group: NL+ or high TGR ≥0.30%/day).

Results

A total of 117 patients (Rapid/Slow groups, 72/45; NIVO/IRI groups, 32/85) were eligible. All baseline characteristics except peritoneal metastases were similar between patients treated with NIVO and IRI in the Rapid and Slow groups. The response rate was significantly higher in patients treated with NIVO compared with IRI [31%/3%; odds ratio (OR), 13.8; P = 0.01; adjusted OR, 52; P = 0.002] in the Slow group, but there was no difference between patients treated with NIVO and IRI (5%/8%; OR, 0.68; P = 0.73; adjusted OR, 0.94; P = 0.96) in the Rapid group. Disease control rate, progression-free survival, and overall survival were consistent with these results.

Conclusions

Our findings suggest that NIVO treatment is a more favorable option for patients with slow-growing tumors, and NIVO and IRI are similarly recommended for patients with rapid-growing tumors in refractory AGC. TGR and NL emergence during preceding treatment may be helpful for drug selection and warrant further investigation.

•

NIVO and IRI are standard treatments for refractory AGC, although it is unclear which should be administered first.

•

TGR may be useful for drug selection, therefore we evaluated the association between TGR and the tumor response to NIVO or IRI.

•

In the Slow group, the response rate (RR) was significantly higher in patients treated with NIVO compared with IRI.

•

In the Rapid group, there was no significant difference in RR between the NIVO and IRI groups.

•

TGR and NL emergence during preceding treatment may be useful for drug selection.

Potential relationship between high wall shear stress and plaque rupture that cause acute coronary syndrome: insights from optical coherence tomography based computational fluid dynamic simulation

Background

The direct relationship between plaque rupture (PR) that cause acute coronary syndrome (ACS) and wall shear stress (WSS) remains uncertain.

Methods

From the Kobe University ACS-OCT registry, one hundred ACS patients whose culprit lesions had PR documented by optical coherence tomography (OCT) were enrolled. Lesion-specific 3D coronary artery models were created using OCT data. Specifically, at the ruptured portion, the tracing of the luminal edge of the residual fibrous cap was smoothly extrapolated to reconstruct the luminal contour before PR. Then, WSS was computed from computational fluid dynamics (CFD) analysis by a single core laboratory. Relationships between WSS and the location of PR were assessed with 1) longitudinal 3-mm segmental analysis and 2) circumferential analysis. In the longitudinal segmental analysis, each culprit lesion was subdivided into five 3-mm segments with respect to the minimum lumen area (MLA) location at the centered segment (Figure. 1). In the circumferential analysis, we measured WSS values at five points from PR site and non-PR site on the cross-sections with PR. Also, each ruptured plaque was categorized into the lateral type PR (L-PR), central type PR (C-PR), and others according to the relation between the site of tearing and the cavity (Figure. 2).

Results

In the longitudinal 3-mm segmental analysis, the incidences of PR at upstream (UP1 and 2), MLA, and downstream (DN1 and 2) were 45%, 40%, and 15%, respectively. The highest average WSS was located in UP1 in the upstream PR (UP1: 15.5 (10.4–26.3) vs. others: 6.8 (3.3–14.7) Pa, p&lt;0.001) and MLA segment in the MLA PR (MLA: 18.8 (6.0–34.3) vs. others: 6.5 (3.1–11.8) Pa, p&lt;0.001), and the second highest WSS was located at DN1 in the downstream PR (DN1: 5.8 (3.7–11.5) vs. others: 5.5 (3.7–16.5) Pa, p=0.035). In the circumferential analysis, the average WSS at PR site was significantly higher than that of non-PR site (18.7 (7.2–35.1) vs. 13.9 (5.2–30.3) Pa, p&lt;0.001). The incidence of L-PR, C-PR, and others were 51%, 42%, and 7%, respectively. In the L-PR, the peak WSS was most frequently observed in the lateral site (66.7%), whereas that in the C-PR was most frequently observed in the center site (70%) (Figure. 3). In the L-PR, the peak WSS value was significantly lower (44.6 (19.6–65.2) vs. 84.7 (36.6–177.5) Pa, p&lt;0.001), and the thickness of broken fibrous cap was significantly thinner (40 (30–50) vs. 80 (67.5–100) μm, p&lt;0.001), and the lumen area at peak WSS site was significantly larger than those of C-PR (1.5 (1.3–2.0) vs. 1.4 (1.1–1.6) mm2, p=0.008). Multivariate analysis demonstrated that the presence of peak WSS at lateral site, thinner broken fibrous cap thickness, and larger lumen area at peak WSS site were independently associated with the development of the L-PR.

Conclusions

A combined approach with CFD simulation and morphological plaque evaluation by using OCT might be helpful to predict future ACS events induced by PR.

Funding Acknowledgement

Type of funding source: None

Morphological plaque characteristics and clinical outcomes of acute coronary syndrome patients with a cancer history

Background

Although previous studies have reported that patients with a history of cancer have 2–3 times higher risks for acute coronary syndrome (ACS), morphological culprit plaque characteristics in ACS patients with a cancer history and their relations with clinical outcomes remain unknown.

Methods

The Kobe University ACS-OCT registry is a multi-center registry of consecutive ACS patients who underwent OCT-guided emergent PCI in Japanese four centers. All patients were categorized into the patients without a history of cancer (non-cancer), those with a history of cancer who diagnosed more than one year before ACS (historical), and those with ongoing cancer treatment or diagnosis within one year before ACS (current). ACS culprit lesions were classified into plaque rupture (PR), plaque erosion (PE), and calcified nodule (CN) according to morphological features by OCT and clinical events were collected after the onset of ACS.

Results

Among 436 patients, 63 patients (14.4%) had a history of cancer or ongoing treatment of cancer (cancer patients). Cancer patients were significantly older than non-cancer patients (73.4±9.4 vs. 66.9±12.9, p=0.001), and non-ST segment elevation ACS was more frequently observed in cancer patients than in non-cancer patients (57.1% vs. 43.2%, p=0.039). Regarding the ACS culprit lesion, the frequency of PR was significantly lower and the frequencies of PE and CN were significantly higher in the cancer patients than in the non-cancer patients (Figure A1). The cumulative incidence of major adverse cardiovascular event (MACE: composite of cardiac death, non-fatal myocardial infarction, and any revascularization, stroke, and heart failure with admission) after the onset of ACS in cancer patients was significantly higher than that in the non-cancer patients (Figure B1). When the cancer patients were categorized into the historical and the current cancer patients, the frequency of PE was higher in the current and the historical cancer patients than the non-cancer patients. Also, the incidence of CN was significantly higher in the historical cancer patients than others (Figure A2). The cumulative incidence of MACE was significantly higher in the current cancer patients, followed by historical and non-cancer patients (Figure B2). Cox regression analyses demonstrated that the non-PR lesion (hazard ratio (HR) 0.65, 0.46–0.94, p=0.021), patients with multivessel disease (HR 2.55, 1.79–3.64, p&lt;0.001), older patients (HR 1.02, 1.00–1.03, p=0.043) were independently associated with MACE after ACS. Moreover, multivariate analysis demonstrated that cancer history (HR 4.64, 2.34–9.21, p&lt;0.001) and non-ST segment elevation ACS (HR 0.66, 2.34–9.21, p=0.038) were independently associated with non-PR lesion.

Conclusions

The present study revealed the difference in morphological plaque characteristics between cancer and non-cancer patients, which might explain potential underlying mechanisms for worse outcomes in cancer patients.

Funding Acknowledgement

Type of funding source: None

P3644Plaque progression from normal vessel wall to fibroatheroma: lessons from over 5-year follow-up optical coherence tomography study

Background

Progression of atherosclerosis is a non-uniform process characterized by coexistence of normal vessel wall (NVW) and advanced fibroatheroma within the same cross-section (Figure). Plaque progression from NVW to fibroatheroma usually takes years, that has never been investigated in human.

Purpose

To investigate the incidence and related factors associated with atherosclerotic progression from NVW to fibroatheroma using long-term serial optical coherence tomography (OCT) follow-up data over 5 years.

Methods

We enrolled 47 vessels in 30 patients who had undergone serial OCT imaging over 5 years (average: 6.8 years). Baseline and follow-up OCT images were matched for longitudinal and circumferential location and OCT cross-sections that had NVW >30 degrees were enrolled. NVW was defined as vessel wall having OCT-detectable three-layer structure with intimal thickening ≤300μm. Cross-sections were diagnosed as +Progression when NVW in the cross-section reduced by >30 degrees during >5-year follow-up.

Results

In the present study, atherogenic progression from NVW to fibroatheroma was observed only in 37.2% of the enrolled cross-sections. On the other hand, despite an average long-term follow-up period of 6.8 years, the extent of NVW was maintained in 62.8% of cross-sections. The incidence of microchannel in adjacent fibroatheroma within the same cross-section (23.6% vs. 13.1%, p=0.023), eccentric plaque distribution (21.7% vs. 11.4%, p=0.019), and concave shape (6.6% vs. 0%, p=0.001) at baseline was significantly higher in cross-sections with +Progression than those without Progression. Average intimal thickness of NVW (187.2±64.9μm vs. 170.7±68.6μm; p=0.048) at baseline was significantly thicker in cross-sections with +Progression than those without. Multivariate analysis demonstrated that the presence of microchannel, eccentric plaque distribution and thicker average intimal thickness of NVW at baseline were independently associated with plaque progression during the follow-up.

Atheroma progression

Conclusion

The presence of microchannel in adjacent fibroatheroma, eccentric plaque distribution, and thicker intimal thickening of NVW were potentially associated with plaque progression from NVW to fibroatheroma.

Pressure-induced stacking disorder in boehmite

The structure of an aluminum layered hydroxide, boehmite (γ-AlOOH), as a function of pressure was studied by using in situ synchrotron X-ray and neutron diffraction. Peak broadening, which is only found for hkl (h ≠ 0) peaks in the X-ray diffraction patterns, is explained by stacking disorder accompanying a continuously increasing displacement of the AlO6 octahedral layer along the a-axis. This finding could be the first experimental result for pressure-induced stacking disorder driven by continuous layer displacement. The magnitude of the layer displacement was estimated from the X-ray scattering profile calculation based on the stacking disordered structure model. Hydrogen bond geometries of boehmite, obtained by structure refinements of the observed neutron diffraction patterns for the deuterated sample up to 10 GPa, show linearly approaching O-D covalent and DO hydrogen bond distances and they merge below 26 GPa. Pressure-induced stacking disorder makes the electrostatic potential of hydrogen bonds asymmetric, yielding less chance for proton-tunnelling.

Abstract P5-22-15: Hormone receptor status is a predictive factor for axillary lymph node recurrence after sentinel lymph node biopsy

Background

Axillary staging is important for predicting prognosis, and for local control in early breast cancer. Sentinel lymph node biopsy (SLNB) is a widely accepted method to avoid unnecessary axillary lymph node dissection (ALND). Since the ACOSOG Z0011 trial was published, we have refrained from ALND for selected patients with positive SLNB results. However, some cases have shown regional lymph node recurrences after SLNB without axillary dissection. The purpose of this study is to identify risk factors for recurrences, to ensure a safe axillary surgery.

Methods

A retrospective review of 1011 patientswho underwent SLNB without ALND between June 2004 and March 2017 was performed. Since October 2012, we have not performed ALND in patients (a) with 1 or 2 positive sentinel lymph nodes (SLNs), (b) with positive SLNs that are unmatted or not gross extra nodal extension, (C) in whom clinical tumor size is &lt;5 cm, and (d) who receive adjuvant endocrine therapy or chemotherapy and radiotherapy. Cases of mastectomy, lumpectomy with a positive margin and additional resection or boost radiotherapy, and bilateral cancer were included. SLNs were identified using technetium sulfur colloid and indigo carmine blue dye, and were bisected in parallel to the long axis of the nodes. The sections were stained with hematoxylin and eosin. Adjuvant systemic and/or radiation treatment was delivered as per the National Comprehensive Cancer Network and the Japanese Breast Cancer Society clinical practice guidelines and was based on the patients' pathological and clinical traits.

Results

Of the 1011 patients, 969 had negative and 42 had positive SLNs. The median age of patients was 59 years (range 21-88). The median invasive breast tumor size was 15 mm (range 0.05-85), with 1.9% tumors being pathological T3 lesions; 127 patients (12.3%) developed lymphatic vessel invasion. SLNs identification rate was 99.4%. The median number of SLNs removed per patient was 2 (range 1-7). After follow-up of a median 78.5 months, 10 patients (1.0%) had an axillary recurrence and all of them had negative SLN metastasis. The median time to axillary recurrence was 26 months (range 9-94). The hormone receptor (HR) status was significantly related to axillary recurrence (p=0.008). While triple negativity had a tendency to relate (p=0.06), human epidermal growth factor receptor 2 (HER2) status did not correlate with axillary recurrence (p=0.13).

Tumor subtypes and axillary recurrence SLNB without ALND (n=1011)Axillary recurrenceP valueHR positive72650.009HR negative1615 HER2 positive12130.13HER2 negative7667 Triple Negative10030.06Not Triple Negative7877 DCIS1240 DCIS: Ductal carcinoma in situ

Conclusions

As reported previously, the axillary recurrence rate after SLNB was low. Our results show that HR negativity was a significant factor for axillary recurrence. Although the ACOSOG Z0011 trial criteria focused on ALNB positive cases, they do not mention the tumor subtypes. Our findings show that HR negative patients without ALND have to follow up carefully.

Citation Format: Sekine C, Nakano S, Mibu A, Otsuka M, Oinuma T. Hormone receptor status is a predictive factor for axillary lymph node recurrence after sentinel lymph node biopsy [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-22-15.

Quality of life following esophagectomy with three-field lymphadenectomy for carcinoma, focusing on its relationship to vocal cord palsy

To clarify the quality of life of patients who underwent esophagectomy for carcinoma by right thoracotomy, laparotomy and cervical anastomosis, 116 patients who were cancer free at the time of mailing a questionnaire were analyzed. A significant decrease in vital capacity for 3 years postoperatively, as well as in the percentage of ideal body weight, between 3 and 5 years were observed in 57 patients with three-field lymphadenectomy. Patients' quality of life undergoing three-field dissection was worse than those with less radical lymphadenectomy (59 cases) in terms of the performance status and difficulty in talking at 60 months or more postoperatively. Around 20% of all patients reported severe hoarseness due to permanent recurrent nerve paralysis, resulting in poor quantity of food intake at 24 months or less postoperatively and restricted daily activity and difficulty in talking at 60 months or more after the operation. When a patient suffers from vocal cord insufficiency caused by permanent paralysis of the recurrent nerve, early treatment before discharge from the hospital should be performed to improve the quality of life of such a patient.

Abstract P4-02-13: Breast ultrasound surveillance with image fusion technique in a short-interval follow-up for BI-RADS category 3 mass lesions

PURPOSE: Breast ultrasound (US) is a diagnostic imaging modality that is now widely used as an adjunct to mammography for evaluation of breast abnormalities. In the Breast Imaging-Reporting and Data System (BI-RADS) lexicon, a solid mass with an oval shape, well-circumscribed margins and parallel orientation is classified as category 3 (BI-RADS category 3 mass lesions) . This mass should have a risk of malignancy of &lt; 2%. Surveillance breast US in short-interval follow-up for BI-RADS category 3 mass lesions is an acceptable alternative to biopsy. The surveillance US is recommended 6 month after initial lesion identification and then every year for at least 2 y. However, inconsistent reproducibility for US due to operator dependence is still a clinical issue. The aim of our study was to verify the utility of US using real-time virtual sonography (RVS) - to coordinate present US images with past US images reconstructed from previously acquired US volume data using magnetic tracking system – in a short-interval follow--up for BI-RADS category 3 mass lesions.

METHOD AND MATERIALS: We enrolled 20 women (23 lesions) with more than 24 months of follow-up after classification as BI-RADS category 3 during initial US. US surveillance was scheduled at 6, 12 and 24 months. Three-dimensional assessment of morphologic features was performed while serially checking past US volume data corresponding to the present US probe position. Measurement of the target lesion diameter was performed after the probe was adjusted to include the maximum diameter of a past US image at each visit.

RESULTS: RVS was technically successful in 100% of patients. All target lesions were detected, including two iso-echoic lesions. The mean target lesion diameters at baseline and at 6, 12 and 24 months were 8.2+4.2, 8.4+4.5, 8.1+4.5 and 8.3+5.0 mm, respectively . Statistical analysis using a Friedman test with multiple comparisons revealed no significant difference between the diameters at each time point (p = 0.785). RVS was used to directly compare the US morphologic characteristics and sized of lesions. Furthermore, the RVS data can be reproduced in their entirety for independent review at a later date by using stored US volume data.

CONCLUSION:Our results suggest that RVS is reproducible, operator-independent technique for comparison of US images of BI-RADS category 3 mass lesions obtained at different time points.

Citation Format: Nakano S, Fujii K, Kousaka J, Mouri Y, Ando T. Breast ultrasound surveillance with image fusion technique in a short-interval follow-up for BI-RADS category 3 mass lesions [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-02-13.